Then, there's some mystery here: even if this seems weird, it is possible to remove the brake pad wires without leaving any visible sign. But when the key of a glovebox is no longer working or lost, you just leave it as is. What I have on my car is a chromed button that perfectly fits the glovebox ... without a hole or a key. So, either this was original or there is a car with exactly the same button but without a key. After looking at pictures on the internet, this obviously doesn't come from a Fiat 124, neither an Alfa Montreal nor a 2000 Dino Coupé. Even the Lamborghini Miura isn't a possible donor for this button. Thus, I really have no idea of the origin of my glovebox button if it's not original...

So this means that at least the french owners manual is speaking of things that might not actually be on the car. Can you confirm your gloveboxes are 2400 ones? As one possibility is that 2000 coupé have the same glovebox as the 2400 but without lock or with a locking system not on the button.

However, I still have another strange thing about this glove box: I do have a push button that is activated by the glovebox opening but I found no clue of a light being installed into the glovebox. Speaking with Mike Morris, he told me that such differences are not something rare on the Dinos and he even told me that for sure, his 1970 2400 Spider had no bake pad ware indicator. But as Coupé and Spider are quite different (one from Bertone, one from Pininfarina), this is not an absolute proof that some Coupé 2400 might have been delivered without brake pad ware indicators.

Not only the French owner manual speaks about this key on page 4 and 8, but not on page 11. Do not take this too serious. Maybe it was panned but not realised. The 2400 Coupe glovebox is totally different from the 2000. The same with the Spider. As Mike has already told you, it may happen that these handcrafted cars differ a bit from each other. I have cables left for the break pad wear indication, but they could be removed without leaving any traces. Maybe this happened to your car.